If you have health issues then you have health issues. If your S.O. puts his own fun over your health then is the relationship built on a level playing field or are you your partner's utility person? As long as you make it ok to be guilted into serving as your boyfriend's chauffeur then you can bet anything that this situation will play itself out again and again. If he insists on making you feel bad that you refused to accompany him on this latest jaunt then you may want to step back and ask yourself what exactly he's contributing to your relationship. You need space to sort things out and he needs time to consider that it may not be the best policy to be taking you for granted. I hope you do feel better.